Spool



Patented Mar. 3, 1925.

. UNITED. STATES 1,528,445 PATENT OFFICE.

NORMAN MARSHALL, OF NASHUA, NEW HAMPSHIRE SPOOL.

Application filed March 4, 1924. Serial No. 696,771.

To all whom it may concern:

Be it known that I, NORMAN MARSHALL, a citizen of the United States, residing at Nashua, in the county of Hillsborough and State of New Hampshire, have invented certain new and useful Improvements in Spools; and I do hereby declare the following to be a full, clear, and exact descrip- -tion of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

. The present invention relates to spools and more particularly to a type of paper or pasteboard spool formed from a central core tube and a pair of end disks secured thereon.

.The object of the present invention is to provide a spool ofthis general nature which can be easily and economically manufactured and which is of sufiicient strength to withstand the usual conditions to which thespool is put in actual use. To this end the invention consists of the spool hereinafter described and particularly defined in the claims.

In the accompanying drawings Fig. 1 is an elevation, partly in section, of the pre ferred form of core tube; Figs. 2 and 3 are detail views showing the manner of heading over ends of the tube to secure the end disks therein; and Fig. 4 is an elevation, partly in section, of the completed spool.

The illustrated embodiment of the invention comprises a central core tube 6 together with a.- pair of end disks 8 which are secured on the ends of thetube. The tube 6 is formed from rolled paper and, as illustrated in Fig. 1, is provided with a taper 10 at each end, the taper being, referably formed by subjecting the ends 0 the tube to the action of a tapering die. This tapering operation does not weaken the tube by the removal of material therefrom but on the contrary strengthens the ends by crowding the fibres into a smaller space so that the thickness of the tapered ends is equal to," or slightly greater than, the thickness of the paper at the center of the tube. The end disks 8, which are placed on the ends of the tube, are-provided with central openings of *suflicient'sizeto be accommodated snugly u on the tapered portion of the tube and to cave a suflicient amount of tube rotruding outside .of the .disk to,,provide ibr heading over the end of the tube to 1 atin secure the disk thereon. This heading operation is preferably performed by the heading tool illustrated in Figs. 2 and 3, which comprises a rotating arbor 12, upon which is secured a heading die 14. r The entrance of the arbor into the end of the tube, as shown in Fig. 2, serves initially to distend the "walls of the tube, thereby causing the inner wall of the disk to be firmly impressed in the material of the core thus forming a I slight shoulder at the point 16. U on further inward movement of the tool w en the heading die comes into engagement with the protruding end of the tube, the latter is rolled down or headed over against the pressure of the die against the disk also serves to push the latter inwardly, accentuthe shoulder 16. The disk is thus secure against inward movement by the shoulder 16 and against outward movement by the headed" over portion 18 of the tube.

' The completely formed spool, as illustrated in Fig. 4, may, if desired, be coated or impregnated at its ends with a hardeningcompound which will give a more secure engagement between the tube and the end disk s. Although a wide variety of substances may be used for this purpose, it has been found that sodium silicate is the most suitable. The ends of the tube may be dipped into or sprayed with a solution 'of sodium silicate, and upon drying the Billcate will form a hard glass-like coating, thus forming a secure bond to retain the disks on the tube.

- side of the disk, as shown in Fig. 3. The

It will be seen that the present invention forms 'a spool of exceedingly substantial construction. The formation of the taper on the core without the removal of any material from the core is an important feature,

because the material which is originally compressed into the taper during the ta ering operation is afterwards ava1lable w hen the tube is headed over to s read out to substantially its original thickness. The

tube is, therefore, of substantial and uniform strength throughout its length, even at the center of the core, a disk with a central opening mounted on each end of the core, the core being headed over at the ends to secure the disks upon the core. I

2. A spool comprising a pa er core tube having the material at its en s compressed to form tapers of a thickness at least as great as the center of the core, and a pair of end disks mounted on the ends of the core, the protruding ends of the core being 10 headed over to secure the disks thereto.

the same thickness as the center of the tube,

and a pair of end disks with circular openings mounted at the ends of the tube, the ends of the tube being headed over and impregnated with a hardening compound to retain the disks securely on the tube.

NORMAN MARSHALL 

